Menopausal Hormone Therapy (Postmenopausal Hormone Use)

Menopausal hormone therapy for women without a history of breast cancer

The use of menopausal hormone therapy (MHT) increases the risk of both developing and dying from breast cancer (learn more) [103-105]. MHT is also known as postmenopausal hormone use or hormone replacement therapy.

Although MHT is approved for the short-term relief of menopausal symptoms, the U.S. Food and Drug Administration (FDA) recommends women use only the lowest dose that eases symptoms for the shortest time needed [106].

Menopausal hormone therapy for women with a history of breast cancer

For breast cancer survivors, avoiding MHT may be more important than for other women. Survivors have an increased risk of getting a second breast cancer and MHT use increases the risk of breast cancer [103-105].

Whether MHT increases the risk of breast cancer recurrence in survivors is still under study. Much of the research done to date has not found a link between the two [107-109]. However, one randomized clinical trial was stopped because the survivors who were taking MHT had more recurrences, metastases and second breast cancers than survivors not taking MHT [110].

Currently, the best choice for most breast cancer survivors is to avoid the use of MHT. Women should discuss other ways to relieve menopausal symptoms with their health care provider.

Bio-identical hormones

There is no medical or scientific definition for the term “bio-identical hormones,” so you may hear this term used in different ways. Some people use it to describe hormone drugs that have the same chemical and molecular structure as hormones found in the body. (Not all products that claim to be bio-identical meet this definition.) “Bio-identical" may also refer to hormone therapies that are custom compounded (when a pharmacist makes a mixture of hormones according to the physician’s instructions on a prescription) [111-113]. No matter the definition, it is important to remember:

Bio-identical hormones have not been shown to be safer than FDA-approved MHT. There is no evidence bio-identical hormones have fewer health risks than FDA-approved MHT. And, because they have not been well-studied, bio-identical hormones may have more health risks [111-112].

Bio-identical hormones have not been shown to be more effective at treating menopausal symptoms than FDA-approved MHT [111-112].

There is no scientific evidence that saliva tests to check hormone levels are useful in making custom compounded hormone therapies [111-112].